Channel Specifications - SC Ports Authority
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Channel Specifications

With the deepest water in the South Atlantic, Charleston offers a maintained harbor of -45 feet (13.7 meters) of depth at mean low tide throughout the main shipping channel and -47 feet (14.3 m) in the entrance channel. A five to six foot tidal lift provides even deeper access for several hours during the day. The following chart illustrates Charleston’s big ship handling capability throughout the day:

Vessel Drafts 43 Ft 44 Ft 45 Ft 46 Ft 47 Ft 48 Ft
Vessel Movement Hours Per Day 24 Hrs 18 Hrs 14 Hrs 10 Hrs 6 Hrs 2 Hrs

Channel Depth (mean low water):

  • Entrance Channel 47 ft (14.3m)
  • Harbor channel and dockside 45 ft (13.7m)
  • Soft mud bottom

Channel Width:

  • Minimum 500 feet (152m)
  • Maximum 1,000 feet (304.8m)

Tidal Currents:

Average 1.5 knots.

In addition, there are virtually no air draft restrictions in the Port of Charleston. Columbus Street Terminal has no air draft limitations. Vessels access the port’s largest facility, the Wando Welch Terminal, as well as the new terminal under construction at the former Navy Base, by sailing underneath the Ravenel Bridge, which allows for 186 feet (56.7 m) of vertical clearance at mean high water. Ships sailing to North Charleston Terminal transit underneath the Don Holt Bridge, with 155 feet (47.24 m) of air draft.


Ravenel Bridge
Air draft 186 ft (56.6m) MHW

Don Holt Bridge (North Charleston Terminal Only)
Air draft 155 ft (47.24m) MHW


NOAA 11524 and 1 1 526.


Required. Charleston Branch Pilot’s Association.


U.S. Coast Guard regulations apply.

Tug and Tow:

Available 24-hours-a-day.


Available at dock.

Radio Contacts:

Harbor Pilots: VHF Channels 13, 14, 16
Moran Towing: VHF Channel 19A
McAllister Towing: VHF Channel 7A


Available on request or click to view online.